Trends in body condition in polar bears (Ursus maritimus) from the Southern Hudson Bay subpopulation in relation to changes in sea ice
Sea ice is declining over much of the Arctic. In Hudson Bay the ice melts completely each summer, and advances in break-up have resulted in longer ice-free seasons. Consequently, earlier break-up is implicated in declines in body condition, survival, and abundance of polar bears (Ursus maritimus Phi...
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2016
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ftunivtoronto:oai:localhost:1807/71848 2023-05-15T15:13:48+02:00 Trends in body condition in polar bears (Ursus maritimus) from the Southern Hudson Bay subpopulation in relation to changes in sea ice Obbard, Martyn Ernest Cattet, Marc R.L. Howe, Eric J. Middel, Kevin R. Newton, Erica J. Kolenosky, George B. Abraham, Kenneth F. Greenwood, Craig J. 2016-02-15 http://hdl.handle.net/1807/71848 http://www.nrcresearchpress.com/doi/abs/10.1139/AS-2015-0027 unknown NRC Research Press (a division of Canadian Science Publishing) N http://hdl.handle.net/1807/71848 http://www.nrcresearchpress.com/doi/abs/10.1139/AS-2015-0027 Article 2016 ftunivtoronto 2020-06-17T11:58:38Z Sea ice is declining over much of the Arctic. In Hudson Bay the ice melts completely each summer, and advances in break-up have resulted in longer ice-free seasons. Consequently, earlier break-up is implicated in declines in body condition, survival, and abundance of polar bears (Ursus maritimus Phipps, 1774) in the Western Hudson Bay (WH) subpopulation. We hypothesised that similar patterns would be evident in the neighbouring Southern Hudson Bay (SH) subpopulation. We examined trends 1980–2012 in break-up and freeze-up dates within the entire SH management unit and within smaller coastal break-up and freeze-up zones. We examined trends in body condition for 900 bears captured during 1984–1986, 2000–2005, and 2007–2009 and hypothesised that body condition would be correlated with duration of sea ice. The ice-free season in SH increased by about 30 days 1980–2012. Body condition declined in all age and sex classes, but the decline was less for cubs than for other social classes. If trends towards a longer ice-free season continue in the future, further declines in body condition and survival rates are likely, and ultimately declines in abundance will occur in the SH subpopulation. The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author. Article in Journal/Newspaper Arctic Hudson Bay Sea ice Ursus maritimus University of Toronto: Research Repository T-Space Arctic Hudson Hudson Bay |
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Open Polar |
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University of Toronto: Research Repository T-Space |
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ftunivtoronto |
language |
unknown |
description |
Sea ice is declining over much of the Arctic. In Hudson Bay the ice melts completely each summer, and advances in break-up have resulted in longer ice-free seasons. Consequently, earlier break-up is implicated in declines in body condition, survival, and abundance of polar bears (Ursus maritimus Phipps, 1774) in the Western Hudson Bay (WH) subpopulation. We hypothesised that similar patterns would be evident in the neighbouring Southern Hudson Bay (SH) subpopulation. We examined trends 1980–2012 in break-up and freeze-up dates within the entire SH management unit and within smaller coastal break-up and freeze-up zones. We examined trends in body condition for 900 bears captured during 1984–1986, 2000–2005, and 2007–2009 and hypothesised that body condition would be correlated with duration of sea ice. The ice-free season in SH increased by about 30 days 1980–2012. Body condition declined in all age and sex classes, but the decline was less for cubs than for other social classes. If trends towards a longer ice-free season continue in the future, further declines in body condition and survival rates are likely, and ultimately declines in abundance will occur in the SH subpopulation. The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author. |
format |
Article in Journal/Newspaper |
author |
Obbard, Martyn Ernest Cattet, Marc R.L. Howe, Eric J. Middel, Kevin R. Newton, Erica J. Kolenosky, George B. Abraham, Kenneth F. Greenwood, Craig J. |
spellingShingle |
Obbard, Martyn Ernest Cattet, Marc R.L. Howe, Eric J. Middel, Kevin R. Newton, Erica J. Kolenosky, George B. Abraham, Kenneth F. Greenwood, Craig J. Trends in body condition in polar bears (Ursus maritimus) from the Southern Hudson Bay subpopulation in relation to changes in sea ice |
author_facet |
Obbard, Martyn Ernest Cattet, Marc R.L. Howe, Eric J. Middel, Kevin R. Newton, Erica J. Kolenosky, George B. Abraham, Kenneth F. Greenwood, Craig J. |
author_sort |
Obbard, Martyn Ernest |
title |
Trends in body condition in polar bears (Ursus maritimus) from the Southern Hudson Bay subpopulation in relation to changes in sea ice |
title_short |
Trends in body condition in polar bears (Ursus maritimus) from the Southern Hudson Bay subpopulation in relation to changes in sea ice |
title_full |
Trends in body condition in polar bears (Ursus maritimus) from the Southern Hudson Bay subpopulation in relation to changes in sea ice |
title_fullStr |
Trends in body condition in polar bears (Ursus maritimus) from the Southern Hudson Bay subpopulation in relation to changes in sea ice |
title_full_unstemmed |
Trends in body condition in polar bears (Ursus maritimus) from the Southern Hudson Bay subpopulation in relation to changes in sea ice |
title_sort |
trends in body condition in polar bears (ursus maritimus) from the southern hudson bay subpopulation in relation to changes in sea ice |
publisher |
NRC Research Press (a division of Canadian Science Publishing) |
publishDate |
2016 |
url |
http://hdl.handle.net/1807/71848 http://www.nrcresearchpress.com/doi/abs/10.1139/AS-2015-0027 |
geographic |
Arctic Hudson Hudson Bay |
geographic_facet |
Arctic Hudson Hudson Bay |
genre |
Arctic Hudson Bay Sea ice Ursus maritimus |
genre_facet |
Arctic Hudson Bay Sea ice Ursus maritimus |
op_relation |
N http://hdl.handle.net/1807/71848 http://www.nrcresearchpress.com/doi/abs/10.1139/AS-2015-0027 |
_version_ |
1766344329546170368 |